Improvement in furnaces for portable boilers



W. J'. F. LIDDELL.

v FURNACES FOR P RTABLE-Bonus. N01174,139. Patented Feb. 29, 1875.

VVEJVITOR N I v J 7 I Attorneys.

UNITED f STATES PATENT QFFIGE.

WALTER J. F. LIDDELL, OF MILWAUKEE, WISCONSIN.

IMPROVEMENT m FURNACES FOR PORTABLE BOILERS.

Specification forming part of Letters Patent No. 174,139, dated February 29,1876; application filed January 3, 1876.

To all whom it may concern: Be it known that I, VVJ. F.LIDDELL, of Milwaukee,in the county of Milwaukee and State of Wisconsin, have invented certain new and useful Improvements in Portable Boilers; and I do hereby declare the following to be a full,

clear, and exact description of the invention,

parts, and is liable to be the initiative cause of injury or damage; and, second, the economizing of the firstcost .of producing steam power, by the employment of the several features herein described, which insures a better draft and a more thorough combustion along the entire length of the furnace.

My invention consists in combining a boiler, the shell of which extends well out into the fire-box, with the latter constructed without a crown-sheet, and provided with the several advantages of draft and equipment, all as at large hereinafter appears.

Heretofore, all boilers of the classin reference have necessitated the common crownsheet, .which is objectionable, both on account of its expense and other attendant disadvantages also, accumulations of fuel at the back of the fire-box have been inaccessible to .circulations of air, and have thus prevented an equal distribution of combustion throughout its length.

Referring to the drawings, Figure 1 is a ver tical longitudinal section of my improvement,

while Figs. 2 and 3 are front and rear end elevations, respectively, of same. p

A is the ordinary vtubular=boiler-shell, with its tubes, water and steam spaces, 860., but prolonged or carried forward well out into the fire-box. This places an extensive horizontal body surface of the boiler directly in the heart of the furnace-fire, and causes the full effect of the latter tov be spent at once upon it.

This extension of the boiler adds the imcrown-sheet, which is its distinguishing characteristic, and is, by its peculiar form, freed from need of same. The strong impact of the flame in its first heat is directed immediately against the lower horizontal casin g of the shell, and the top casing of the fire-boxis thus relieved from such direct influence of the flame, only the spent and cooler force of the fire reaching it. The furnace-doorO is situated on a plane of level lower than that of the boiler, thus protecting the upright casing of the lat ter from any injury which might be occasioned by the haste or carelessness of the stoker in feeding the fire, and also shielding the said casing from drafts of air consequent upon swinging open the door when hung on a higher line of level.

This fire-box may be lined and protected from the heat, as is agreeable; either the wellknown water-lining, fire-tile, or any suitable' casing may beused. The grateD is supported sufficiently above the bottom of the firebox, so that space may intervene for the ashpan B, and also afford ventilation through one or both of the two door-openings E F, placed, respectively, at the front and rear end of the ashpan, which doors also come into play in cleaning out the ash-pan, &c.

It if observed that the fire-box is constructed with its bottom serving the purpose of an ash-pan of itself, and that the said bottom and sides of the fire-box are of one single piece of metal, G.

A damper, H, is placed at the back of the fire-box, and just above the level of the gratebars to admit air to the surface of the fuel,

since accumulations of the latter at the rear of the fire-box not infrequently clog and choke the progress of combustion, and are unable to be thoroughly ignited, on account of their be ing inaccessible to currents of air. This latter feature of mine effects a perfect and equal distribution of combustion the, entire length of the grate. I

Q' I Lise This damper B may heoonnected by suita ble interveningmechanism With the cab of the *eugine, so that it shall be under the control of the fireman, and any desired air admitted to the fire-box while the locomotive is in inotion.

Having thus described my invention, what.

I claim as new, and desire to secure by Letters Patent, is--- 1. The combination, with tubular boiler A,

the same'having its tube-sheet entirely cover ing its rear end,of the fire-box B,rformed to present thefull area of the rear tnbe-sheetto the action of the flames, substantially asand for thepnrpose set forth.

2. The fire-box B, having the ash-pan Bi 'formed as a part of the same, in combination specified.

In testimony that I claim the foregoing I have hereunto set my hand.

WALTER JAMES FORBES LIDDELL, I

Witnesses: -r

- W. -W.- BELL,

r W. H. G. Soon. 

